While the Riksbank can focus exclusively on Sweden, the ECB has a more complicated task, having to ‘oversee’ a bunch of countries.
Both central banks have an exclusive mandate: “Price stability”. While in Sweden that is understood as 2% inflation, in the EZ it is something slightly lower.
Nevertheless, the two ‘countries’ central banks acted in tandem, tightening as a reaction to higher than target inflation due to oil price shocks. Not surprisingly, they ended up in the same “alley”, but the EZ side of the “alley” is a bit “darker” because of its more diffuse clientele.
This is certainly more evidence against inflation targeting. It´s a “guide dog” that can easily lead you astray!
PS The US turned out different because, although it fell into the “first trap”, it didn´t repeat the mistake. Instead it did QE. Australia did even better because it didn´t fall even into the first trap, keeping NGDP evolving close to trend!